The far north is bearing the brunt of global warming, and, as much of Lapland’s population relies on its polar climate for their livelihoods, the effects are starting to be felt.

Rovaniemi, the administrative capital of the Finnish province of Lapland, has done a good job of capitalising on the region’s Christmas-themed reputation. It is the self-proclaimed “Official Hometown of Santa Claus”, where the man himself can be visited 365 days a year.

However, with his official residence there only constructed in 1950, Santa Claus is a relative newcomer to Lapland.

The wider region is the ancient home of the indigenous Sami people, who refer to it as Sapmi. Owing to its remote location and freezing temperatures, much of Lapland remains relatively pristine wilderness, and it is this wilderness that provides the Sami with space to practise their ancient tradition of reindeer herding.

As temperatures rise and begin to disrupt the unspoiled environment, the future prosperity of all Lapland’s inhabitants – from the Sami to Santa Claus – is at risk.

Dr Stephanie Lefrere first came to Finnish Lapland 18 years ago to study reindeer behaviour. Since then, she has observed dramatic changes in the region’s weather patterns, and subsequent effects on its wildlife.

“In my very first fieldwork, 300km (186 miles) above the Arctic Circle, it was 20°C below zero on 31 October – really the Arctic feeling by the end of October,” she said. “We don’t have that any more.

“Recently there have been ‘black Christmases’ with no snow at all in the southern part of Finland."

Decades of work in the region have cemented her view that climate change is having far-reaching effects on Lapland’s environment, affecting animal migratory routes, habitats and behaviour.

“I became worried as a scientist, and also as an individual who is fascinated by the Arctic,” said Dr Lefrere.

She emphasised that climate change is more about trends over long periods than personal observations. However, her experiences are mirrored by figures from the Finnish Meteorological Institute, which states Finland’s annual mean temperature has risen by over 2°C since the mid-19th century.

“It was my childhood dream to come to Lapland, and to me it has been devastating to see changes occurring so rapidly,” said Dr Lefrere.

These changes are particularly devastating for the people who understand the region better than anyone: the Sami.

“The entire Sami culture circulates around nature and the reindeer,” said Jannie Staffansson, an environmental chemist and indigenous rights activist at the Saami Council. “We are herders, fishers, gatherers and hunters.”

Sami society has always revolved around reindeer, but today Ms Staffansson estimates only 10 per cent of Sami people are still reindeer herders or owners.

“It’s extremely difficult work to do, both physically and mentally, because you are so challenged keeping the reindeer safe and happy, and trying to combat climate change at the same time,” says Ms Staffansson.

Like Dr Lefrere, the reindeer herders have become acutely aware of the impact climate change is having on their animals.

Unpredictable weather patterns and specifically rain replacing snow during the coldest months lead to crusts of ice forming on the ground, where normally there would be a soft layer of snow.

Reindeer, which typically feed by digging into the snow and grazing on lichen, are unable to either smell food under the ice or dig to access it.

“You can have herds starving to death just because they didn’t dig for food,” said Ms Staffansson.

She emphasised the role that reindeer have in shaping everything from the Sami language to their handcrafting traditions, which rely on products like reindeer skin and antlers.

“It’s an entire culture that would disappear with the reindeer,” she said.

The Sami are not the only people of Lapland affected by climate change. In northern Finland, tourism is a cornerstone of the regional economy, but warming temperatures are beginning to threaten its “winter wonderland” image.

“Operators in certain areas are highly concerned,” said Dr Kaarina Tervo-Kankare, a tourism geographer at the University of Oulu in central Finland. “My studies have mainly focused on the perceptions of tourism stakeholders, and their observations support the view that changes have taken place.”

Commonly reported changes are the late arrival of the permanent layer of snow required for winter activities, as well as the increased unpredictability of the weather. Some in the Finnish tourism industry are beginning to diversify their offering, developing their summer activities in areas that have traditionally been winter destinations.

Aside from its status as a Christmas destination, the Finnish Environment Institute predicts that climate change could affect the country’s attraction for fans of winter sports.

There are fears in the industry that climate changes could drive people away from places like Rovaniemi that have established themselves as go-to Christmas destinations, especially as the “black Christmases” described by Dr Lefrere begin to creep northwards.

A study by Dr Tervo-Kankare and her colleagues found that Christmas tourism businesses were already feeling the heat, and that tourists did not react well to their attempts to adapt their offering.

“In the light of climate change projections, maintaining the attractive image of a snow-covered winter wonderland may become impossible,” they wrote.

With Santa Claus Village attracting 300,000 visitors annually, Rovaniemi can ill afford to lose its tourism, but according to Dr Tervo-Kankare this is a possibility for popular Lapland tourist destinations.

“Tourists may head further north or east, where snow security is higher,” she said.

“The image may suffer to the extent where Lapland is no longer recognised as a Christmas destination.”